Headlight reflector



March 31, 1925. 1,531,334

E. A. GOERTZ ETAL HEADLIGHT REFLECTOR Filed Aug, 22, 1923 mzfba; fr /n A. 60602 Wd/fer hf Aroenke may 12/ Patented Mar. 1 925.

UNITED, STATES ERVIN GOERTZ AND WALTER H. KROENKE, OF FARIBAULT, MINNESOTA.

HEADLIGHT REFLECTOR.

' Application ma August 22,- 1923. Serial No. 658,711.

To all whom it may concern:

and WALTER H. Knomrxn, citizens of the United States, residing at Faribault, in the county of Rice and State ofMinnesota, have invented certain new and useful Improvements in Headlight Reflectors; and we do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled-in the art "to which it appertains to make and use the same.

Our invention relates to headlightreflectors such as used in connection with automobiles and similar vehicles for lighting the road ahead of the machine. The object of the invention is the provision of a reflector which will throw all or substantially all of the light onto the road for the purpose of illuminating the road, thereby, at the same time, eliminating upwardl pro ect1ng rays such as would produce b inding eflects 1n the'eyes of persons in approachmg machines. In carrying out the'mvention, we provide a reflector that will throw all of the reflected rays .onto the road ahead of the machine and will spread the light beam laterally, so as to give full road illumination and give illumination in turning corners or curves. Some of the direct rays will have a slight upward projecton, but such upwardly projected rays will produce only a mild overhead illumination such as desirable to enable the driver to see overhanging objects, such as tree limbs, and will not produce a blinding glare in the eyes of persons in approaching machines.

In the accompanylng drawlngs, we have illustrated a reflector that'illustrates 0ur in-- cause an ordinary circular lens or glass cover late may be em loy'ed in connection therewlth, and second ause the reflector in front elevation will have much the ap- Be it known that we, ERVIN A. GOERTZ pearance of an ordinary reflector.

The reflector is indicated as an entirety by by the numeral 4 and its axis is substantially on the I line a-o. Projected through the bak of the reflector on the axis thereof is a light bulb socket 5 that holds a light bulb 6 in position within the reflector with its cen-' ter or hot spot of its filament on the axis a I) substantially at a. This reflector has radial sections that vary greatly in their lines or curves from the upper vertical radial tor is approximately horizontally extended on an approximately straight line; from the point I) to point e, the radial section of said reflector is a hyperbolic curve or approximately such curve. In horizontal radial sections on the line 3-3, (see Fig. 3), the reflector has elliptical or substantlally elliptical curves from the axial point 6 to the rim points f. The oblique radial sections of the reflector will vary progressively from the one to the other of the curves above 'described. In that portion of the reflector that is above the plane of the axis a-a, the elliptical or approximately elliptical curves bf inay be blended into the curve b-0-d in any suitable way but preferably as gradually as possible. In that portion of the reflector that is below the plane of the axis aa, the

radial sections are preferably all comes; and,

progressing from the conic curves bf, which have an eccentricity less than one, into the hyperbolic curves be, which have an eccentricity greater than one, the variation in curve willproduce in the reflector an oblique-radial section having a parabolic curve or conic with an eccentricit of one, approximately at the oblique ra ial sections that are at an angle of 45 to the horizontal plane of the axis H In Figs. 2-and 3, the broken lines indicate certain of the refl'ected rays, and in Fig. 2

the dotted line indicates the uppermost oi the direct rays. I

By reference first to Fig. 2, it will be noted that the light bulb is located close to the approximately horizontal hood or top portion downward onto the road ahead of the machine. It will also be noted that-the reflected rays that strike the lower portion of the reflector will be projected downward onto the road, so that all of the reflected rays reach the road and only-part of the direct .rays are projected above the horizontal plane of the axis a. p

By reference to Fig. 3, it will be noted that the reflected rays, on striking thc elliptical curves 6- are crosswise projected in front of the re ector and spread out on oposite sides of the reflector so as to give the e'sired wide road illumination. Only a comparatively small part of the reflected rays will, however, be thus widely spread on the road, for most of the rays and the most intense rays will be projected onto the road within a comparatively small lateral space so" as to give the most intense illumi I nation on the road to be traveledby the machine.

The above described arrangement gives P substantially an ideal distribution of the light. It gives the desired mild overhead illumination, the desired mild illumination at the sides of the road, and the more intense illumination on the road proper that is to be traveled by the machine. Thus, no

light is actually wasted and the best possible illumination is producedand blinding glare is eliminated. This reflector will produce a light beam that will meet the requirements of the illumination-regulating ordinances or laws of the various different states and cities. The reflector may be stamped to form at no greater cost than that of an ordinary reflector and it is ada ted to be used with a plain or simple clear g ass lens or cover plate.

What we claim is:

A head light reflector set on a horizontal axis and combined with a light bulb, the back of the reflector above the horizontal axis of the light bulb being concentric with the ,focal point of the light bulb and terminating at the vertical axis thereof, the top of the reflector being parallel to the horizontal axis of the light bulb and extending tangentially from said back and the lower portion of the reflector below the horizontal axis of the light bulb following the line of hyperbolic' curve, said reflector in the horizontal lane of its axis follows an elliptical curve and the rim of said reflector is round.

In testimony whereof we aflix our signatures.

ERVIN A. GOERTZ. 1 WALTER H. KBOENKE. 

